package cn.itcast.hotel.service.impl;

import cn.itcast.hotel.mapper.HotelMapper;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.geo.GeoPoint;
import org.elasticsearch.common.unit.DistanceUnit;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.functionscore.FunctionScoreQueryBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService {

    @Autowired
    private RestHighLevelClient client;

    @Override
    public void insertByid(Long id) {
        try {
            // 0.根据id查询酒店数据
            Hotel hotel = getById(id);
            // 转换为文档类型
            HotelDoc hotelDoc = new HotelDoc(hotel);

            // 1.准备Request对象
            IndexRequest request = new IndexRequest("hotel").id(hotel.getId().toString());
            // 2.准备Json文档
            request.source(JSON.toJSONString(hotelDoc), XContentType.JSON);
            // 3.发送请求
            client.index(request, RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void deleteByid(Long id) {
        try {
            // 1.准备request
            DeleteRequest request = new DeleteRequest("hotel",id.toString());
            // 2.发送请求
            client.delete(request, RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public List<String> getSuggestions(String key) {
        try {
            // 1.准备request
            SearchRequest request = new SearchRequest("hotel");
            // 2.准备DSL
            request.source().suggest(new SuggestBuilder().addSuggestion("suggestions",
                    SuggestBuilders.completionSuggestion("suggestion")
                    .prefix(key)
                    .skipDuplicates(true)
                    .size(10)
            ));
            // 3.发送请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            // 4.解析结果
            Suggest suggest = response.getSuggest();
            // 4.1根据名字获取结果
            CompletionSuggestion suggestions = suggest.getSuggestion("suggestions");
            // 4.2获取options
            List<CompletionSuggestion.Entry.Option> options = suggestions.getOptions();
            // 4.3遍历
            ArrayList<String> list = new ArrayList<>();
            for (CompletionSuggestion.Entry.Option option : options) {
                list.add(option.getText().toString());
            }
            return list;
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public Map<String, List<String>> filters(RequestParams params) {
        try {
            // 1.准备request
            SearchRequest request = new SearchRequest("hotel");
            // 2.准备DSL
            // query
            buildBasicQuery(params, request);
            // 2.1设置size
            request.source().size(0);
            // 2.2聚合
            buildAggregation(request);
            // 3.发送请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            // 4.解析聚合结果
            HashMap<String, List<String>> map = new HashMap<>();
            Aggregations aggregations = response.getAggregations();
            // 根据名字获取结果
            ArrayList<String> brandList = getAggByName(aggregations,"brandAgg");
            // 4.4放入map
            map.put("品牌", brandList);
            // 根据名字获取结果
            ArrayList<String> cityAggList = getAggByName(aggregations,"cityAgg");
            // 4.4放入map
            map.put("城市", cityAggList);
            // 根据名字获取结果
            ArrayList<String> starNameList = getAggByName(aggregations,"starNameAgg");
            // 4.4放入map
            map.put("星级", starNameList);
            return map;
        } catch (IOException e) {
            throw new RuntimeException();
        }
    }

    private ArrayList<String> getAggByName(Aggregations aggregations,String aggName) {
        // 4.1根据名称获取聚合结果
        Terms brandTerms = aggregations.get(aggName);
        // 4.2获取桶
        List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
        // 4.3遍历
        ArrayList<String> brandList = new ArrayList<>();
        for (Terms.Bucket bucket : buckets) {
            // 4.4获取key
            String key = bucket.getKey().toString();
            brandList.add(key);
        }
        return brandList;
    }

    private void buildAggregation(SearchRequest request) {
        request.source().aggregation(AggregationBuilders
                .terms("brandAgg")
                .field("brand")
                .size(100));
        request.source().aggregation(AggregationBuilders
                .terms("cityAgg")
                .field("city")
                .size(100));
        request.source().aggregation(AggregationBuilders
                .terms("starNameAgg")
                .field("starName")
                .size(100));
    }

    @Override
    public PageResult search(RequestParams params) {
        try {
            // 1.准备Request
            SearchRequest request = new SearchRequest("hotel");
            // 2.准备DSL
            // 2.1query
            buildBasicQuery(params, request);

            // 2.2分页
            Integer page = params.getPage();
            Integer size = params.getSize();
            request.source().from((page - 1)*size).size(size);
            // 2.3根据离我最近排序
            if(params.getLocation() != null && !params.getLocation().equals("")){
                request.source().sort(
                        SortBuilders.geoDistanceSort("location",
                                new GeoPoint(params.getLocation()))
                                .order(SortOrder.ASC)
                                .unit(DistanceUnit.KILOMETERS)
                );
            }

            // 3.发送请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            // 4.解析响应
            return handleResponse(response);
        } catch (IOException e) {
            throw new RuntimeException();
        }
    }

    private void buildBasicQuery(RequestParams params, SearchRequest request) {
        // 1.构建布尔Query
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        // 关键字搜索
        String key = params.getKey();
        if (key == null || "".equals(key)){
            boolQuery.must(QueryBuilders.matchAllQuery());
        }else {
            boolQuery.must(QueryBuilders.matchQuery("all", key));
        }
        // 城市过滤
        if(params.getCity() != null && !params.getCity().equals("")){
            boolQuery.filter(QueryBuilders.termQuery("city", params.getCity()));
        }
        // 品牌条件
        if(params.getBrand() != null && !params.getBrand().equals("")){
            boolQuery.filter(QueryBuilders.termQuery("brand", params.getBrand()));
        }
        // 星级条件
        if(params.getStarName() != null && !params.getStarName().equals("")){
            boolQuery.filter(QueryBuilders.termQuery("starName", params.getStarName()));
        }
        // 价格条件
        if(params.getMinPrice() != null && params.getMaxPrice() != null){
            boolQuery.filter(QueryBuilders.
                    rangeQuery("price").
                    gte(params.getMinPrice()).
                    lte(params.getMaxPrice()));
        }

        // 2.算分控制
        FunctionScoreQueryBuilder functionScoreQuery =
                QueryBuilders.functionScoreQuery(
                        // 原始查询，相关性算分的查询
                        boolQuery,
                        // function score的数组
                        new FunctionScoreQueryBuilder.FilterFunctionBuilder[]{
                                // 其中的一个function score 元素
                                new FunctionScoreQueryBuilder.FilterFunctionBuilder(
                                        // 过滤条件
                                        QueryBuilders.termQuery("isAD", true),
                                        // 算分函数
                                        ScoreFunctionBuilders.weightFactorFunction(10)
                                )
                        });

        request.source().query(functionScoreQuery);
    }


    // 4.解析响应
    private PageResult handleResponse(SearchResponse response) {
        SearchHits hits = response.getHits();
        // 4.1获取总条数
        long total = hits.getTotalHits().value;
//        System.out.println(total);
        // 4.2文档数组
        SearchHit[] hits1 = hits.getHits();
        // 4.3遍历
        ArrayList<HotelDoc> list = new ArrayList<>();
        for (SearchHit documentFields : hits1) {
            // 获取文档
            String json = documentFields.getSourceAsString();
            // 反序列化
            HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);
            // 获取排序值
            Object[] sortValues = documentFields.getSortValues();
            if(sortValues.length > 0){
                Object sortValue = sortValues[0];
                hotelDoc.setDistance(sortValue);
            }
            list.add(hotelDoc);
        }
        return new PageResult(total, list);
    }

}
